Ellers

John Jording Ellers appeals the judgment following his jury conviction of sale of heroin (Health & Saf. Code, § 11352 (count one)) and being under the influence of heroin (Health & Saf. Code, § 11350 (count three)). For the reasons we discuss below, we affirm the judgment as to count one and reverse as to count three.

Factual Background

On March 2, 1977, Michael Becker and the El Cajon Police Department entered into a written agreement providing for the dismissal of burglary charges against Becker and his girlfriend if Becker would buy some heroin and disclose the identity of the dealer. Becker identified the dealer as Ellers.

After being searched, Becker went with Detective Lowery in an unmarked police vehicle to a place about 100 yards from Ellers’ residence in El Cajon. They waited inside the car for Ellers’ arrival. Lowery gave Becker $30 in cash, including a $20 bill and a $10 bill, to buy heroin. After spotting Ellers, Lowery drove down the street and into a driveway next to Ellers’ residence. Becker approached the front door of Ellers’ apartment, through which he saw several people standing inside the apartment. Ellers invited him in. Upon entering, he saw other…