The D.C. statehood convention gave preliminary approval yesterday to a provision in its proposed constitution that would permit government employes--including police, fire and hospital personnel--to strike, except in certain narrowly drawn circumstances.

In a series of heated and sometimes impassioned debates that pitted leftist and more ideological delegates against conservative and more pragmatic factions, the convention narrowly defeated a proposal that would have given an unlimited right to public workers to strike.

Both federal and D.C. government employes currently are barred by law from striking, as are government workers in most states.

"Labor is a commodity . . . It is all we have to bargain with," declared Ward 1 delegate Maurice Jackson, prime mover of the unlimited-strike provision and a Communist Party, USA, organizer.

"The right to strike by anyone is a basic right, an unabridgable right," said Ward 1 delegate Richard Bruning, one of several socialists in the convention.

Not so, countered Ward 3 delegate Courts Oulahan, a Republican. "There is no fundamental right for public employes to strike," he said.

Ward 4 delegate William Cooper, another Republican, warned there is no precedent for public employe strikes in other state constitutions and inclusion of it here would be a "red flag" to Congress to reject the city's proposed constitution.

The Jackson proposal ultimately was defeated by a 14-to-16 vote, with three delegates abstaining. The convention next rejected by a 29-to-0 vote a proposal to exempt police, fire and health care personnel from the right to strike. It then went on to approve what amounted to compromise language proposed by the convention's economic development committee, permitting strikes under limited circumstances. That vote was 22 to 8 with one abstention.

The committee provision says the right to strike may not be abridged unless there is a "compelling governmental interest" and "no alternative form of regulation is possible which does not abridge such right." Convention general counsel Ralph C. Thomas III said this would permit sanitation workers to strike, for example, but if it caused a health hazard because of uncollected refuse in the streets, the state could act to stop the strike.