By Petition for Delinquency it was represented that appellant committed several offenses against two police officers; (1) aggravated assault, (2) unlawful obstruction or opposition of the officers in the performance of their legal duties, (3) resisting arrest without violence and/or aggravated assault, and (4) battery on the same officers, all arising out of a single episode. Appellant brings this appeal from an adjudication of delinquency on each charge. We reverse because the trial court erred in restricting cross-examination of the state’s witnesses on issues going to bias and credibility.

The two officers were the state’s only witnesses. On cross-examination defense counsel sought to establish that both officers had visited defendant’s home prior to the date of the alleged offenses and that based on events of that visit, defendant’s sister had filed charges against both witnesses. The court sustained the state’s objection to the line of questioning.

The right to confrontation under the Sixth and Fourteenth Amendments may in certain cases require an opportunity to develop issues of bias by cross-examination. Davis v. Alaska, 415 U.S. 308, 94 S.Ct. 1105, 39 L.Ed.2d 347 (1974). All witnesses are subject to cross-examination for the purpose of discrediting them by bias, prejudice or interest and this is particularly so where a key witness is being cross-examined. Jones v. State, 385 So.2d 132 (Fla. 4th DCA 1980); Webb v. State, 336 So.2d 416 (Fla. 2d DCA 1976). The discretion normally accorded the trial court concerning the scope of cross-examination was clearly abused in this case.

The adjudication of delinquency is reversed and the cause remanded for a new hearing.