The Post is certainly predictable. It opposed the democratic process of voter Initiative 17 in 1984 and again in 1990 {"The Homeless Referendum Effort," editorial, Aug. 10}. It is only through referendums and initiatives that the people of Washington have the opportunity to hold public officials accountable when they fail to meet the mandates of their constituents. If the D.C. government was meeting the needs of its people, Initiative 17 would be unnecessary.

The reality, however, is that even after a court order and $2 million in fines, this city still refuses to follow the law that 72 percent of the voters demanded in 1984: basic overnight shelter for those District residents who require it. It has become painfully obvious that D.C. officials will not act on their own. And all of the pressing needs The Post listed in its Aug. 10 editorial have a direct connection to homelessness and the lack of decent affordable housing:

Single mothers with children are the fastest growing group among the homeless population and to whom 75 percent of the homeless monies go. Programs for their children will mean nothing if they don't even have a roof over their heads. There is a huge hidden population of homeless teenagers and only one private program to serve them. Finding a home has to be the first step in assisting them.

Health-care costs for those living on the streets are astronomical, exacerbated by the condition of homelessness. An alarming number of homeless people are turning up HIV-positive or are becoming homeless as a result of AIDS. Again, a problem made more difficult and expensive by the lack of shelter and housing.

The D.C. Department of Mental Health has failed for over a decade to provide for our mentally ill and handicapped, once more, even under a court order. The shelter system has become the only haven for these fragile citizens.

What The Post editorial did not mention is that in spite of mismanaged shelter programs, court-ordered fines and growing needs, in 1989 less than 1 percent of D.C. taxpayer dollars went to the homeless budget.

The truth is that our most vulnerable citizens generally do not vote, are not big consumers and don't fund campaigns. Without clearly defined entitlements they will continue to be ignored by this administration and the next. We must save Initiative 17. CAROL FENNELLY DANA BOWDEN Washington The writers are members of the Com- munity for Creative Non-Violence