CCTV footage has been released in relation to the attack on Louis Stanton, also known as Hone Ma Heke, in the early hours of Wednesday morning.
Police would like to speak with the man in this photo.
A police spokesperson was unable to confirm the reasons for wanting to speak to him.
The incident occurred outside the Nelson City Council office at about 6.45am when Louis was attacked with a solvent chemical.
He was admitted to Nelson Hospital with solvent burns to his mouth and throat.
Samples of the substance will be sent away for analysis today.
The car is believed to be a silver or grey Nissan Pulsar or Primera with a rear spoiler and possibly chrome mag wheels.
Anyone with information as to who this person is should contact Detective Constable Dan Shields at Nelson Police Ph 5463840.