The lead investigator was seeking to clarify earlier comments by police that suggested some of the driver's actions were deliberate.
Band members Kris Leonard, River Reeves, Jack Dakin and Tomas Lowe died, along with manager Craig Tarry, 33, near Stockholm on 13 February.
Lars Berglund said the driver's "only intention was to avoid a crash".
Witnesses reported seeing the car going though red lights and barriers before the Warrington band's car plunged 80ft (24m) into a canal off a bridge, the middle section of which was raised.
Mr Berglund told Mirror reporter Rhian Lubin: "I have not suggested that [the driver] was doing this in order to kill himself or the band. I said he was making a move from the right lane to the left lane and that was not accidental.
"We can see the brake lights. His intention was to stop the car. But maybe his speed was too high and it was too late."
Earlier, a Stockholm police spokesman said: "It looks like he [the driver] tried to drive past red lights, barriers.
"All the witnesses thought it looked like he was trying to drive past... there weren't supposed to be cars on the left.
'It is a possibility he deliberately crashed the car, but he may have misunderstood the signs.
"[It is] still subject to investigation and we are still waiting for results of technical investigation too."
Police have previously confirmed the driver, who has not been identified, had no traces of alcohol or drugs and said it would have been very difficult to pass two lines of parked cars if he was asleep.
The car, carrying the four members of the band and their manager, was recovered from the canal under the E4 highway bridge in Sodertalje, Sweden.
In the week after the accident, the band reached number one in the iTunes chart following a social media campaign backed by Oasis singer Liam Gallagher and Tim Burgess from The Charlatans.
A concert in the band's memory at Warrington's Parr Hall on 2 April has now sold out.
The gig, which will feature friends and bands they have played with, will be hosted in their Warrington hometown by BBC Radio 1 DJ Phil Taggart.
Swedish police say they do not believe the Viola Beach crash driver "intended to kill himself or the band".