Last fall the federal government, racing to extricate itself from a relationship with homeless activist Mitch Snyder, embraced the D.C. Coalition for the Homeless and gave the group $3.7 million in a fast-track effort to establish an alternative shelter to Snyder's.

Recently, U.S. Department of Health and Human Services officials suspended part of the grant amid allegations that the coalition -- which critics have claimed was ill-equipped to handle such a large infusion of money and to start a major shelter operation virtually overnight -- has misspent funds and failed to screen its new employes properly.

The tangled conflict that centers on the coalition illustrates the sometimes tumultuous politics of homelessness in the District, marked by shifting alliances among the coalition, Mayor Marion Barry, the federal government and Snyder's advocacy group, the Community for Creative Non-Violence.

"I think the coalition has been dumped on a number of times and has been used a number of times by people," said Snyder. "That is the nature of Washington. That is the nature of politics. It makes for strange bedfellows."

In the past two years, political alliances have seen Barry standing with the coalition against Snyder; Barry standing with Snyder against the coalition and the federal government, and, most recently, the federal government acting in harmony with Snyder and Barry while the mayor and HHS officials distance themselves from the coalition.

The coalition's current problem arises on the threshold of an April 30 deadline for closing the group's temporary men's shelter in Anacostia, with $2 million in grant money unspent and now in doubt. Compounding the problem for the organization, the federal government last month rehabilitated its relationship with Snyder long enough to propose transferring the CCNV shelter from federal hands to the District along with $5 million in renovation funds.

"I think 'dumped out the back door' would be a harsh way" to describe the coalition's problem, said a District official. "They weren't promised a marriage, just an evening of fun."

The coalition, according to President Elisabeth Huguenin, is made up of about 800 churches, community organizations, shelter providers and individuals concerned with the plight of the homeless.

The current investigation by the D.C. police and the FBI into allegations against coalition members has its roots in the federal government's decision last fall to call on the coalition to replace Snyder's CCNV as the principal provider of shelter in the city. Officials of HHS and CCNV, who had reached an agreement in November 1984 to renovate the CCNV shelter, clashed in late spring 1985 over the extent of the renovation.

"HHS decided last fall in the heat of the decision to try to evict Mitch Snyder to try to create an alternative," said D.C. City Administrator Tom Downs.

Another city official said, "I think the feds were between a rock and a hard place, and the most logical group was the coalition, as opposed to one shelter provider. Unfortunately, the coalition was not exactly equipped. They got a lot of money they were not organized to handle."

With winter approaching, HHS officials were under pressure to demonstrate to the U.S. Court of Appeals, which was hearing a challenge brought by Snyder, that the coalition could develop a viable shelter program. The plan proposed by the coalition and HHS called for the federal government to give the coalition $3.7 million to enable the group to open a temporary facility in Anacostia and subsequently establish permanent shelter sites around the city.

One area the investigators are probing is real estate transactions carried out by coalition officials last fall as they were hurrying to show the court that they had identified prospective shelter sites. In particular, investigators are examining the coalition's decision at the urging of board member Lawrence Guyot to pay $21,000 to D.C. police Officer Vernell R. Tanner for rent on a property Tanner had contracted to buy but did not yet own.

Guyot, who is a D.C. Department of Human Services official, said he initially turned to Tanner to lease a property at 1301 T St. NW to satisfy the court. "The court gave us a matter of days," he said.

Subsequently, Guyot said, the coalition determined that the T Street site was inadequate, and Tanner offered a building at 1333 Emerson St. NW, for which the group paid $21,000 for six months' rent. Guyot and Tanner have denied any wrongdoing.

Police and the FBI also are investigating a $1,000 payment made by a contractor for the coalition to Dennis Bethea, who was then a coalition board member as well as the $44,928-a-year chief of the D.C. Office of Emergency Shelter and Support Services. Bethea, who resigned both posts after the payment was discovered, has described it as a loan and said he did nothing illegal.

Bethea has been a central figure in the changing politics of homelessness. In the summer of 1984, Bethea and Guyot, along with other coalition members, actively campaigned against Initiative 17, a ballot item supported by Snyder's group that called for the city to guarantee shelter to the homeless.

Barry was allied with the coalition in opposing the initiative, which was approved by the voters but was subsequently ruled invalid by the courts. Bethea, within months after the election, was appointed the first chief of the city's newly created agency to coordinate services to the homeless.

By last fall, however, Barry was criticizing the coalition's Anacostia plan, even as Bethea and Guyot continued to serve on the board of the organization. Barry had joined forces with Snyder during the summer in opposing the federal government's efforts to sever its ties with Snyder, fearing that such a break would force the city to assume responsibility for hundreds more homeless persons.

Barry, in a statement yesterday, reiterated that the District government plays no role in the operation of the Anacostia shelter -- "a program that we opposed from the very beginning."